#!/bin/sh

program_linux='
#include <netinet/in.h>
#include <sys/socket.h>
#include <netdb.h>
'

program_freebsd='
#include <netinet/in.h>
#include <sys/socket.h>
#include <netdb.h>
'

system=$(uname -s)

case $system in
    Linux)   PROGRAM=$program_linux;;
    FreeBSD) PROGRAM=$program_freebsd;;
    *)       echo $0: $system is unsupported >&2; exit 1;;
esac

KIND=$1
KIND=${KIND:-"SocketType,SocketLevel,SocketOption,AddrFamily,AddrInfoFlag,NameInfoFlag"}

echo module netio
echo
echo '/*'
echo -e "\tThis file is generated by mkconst.sh, DO NOT EDIT."
echo '*/'
echo

echo "$PROGRAM" | ${CC:-"cc"} -x c - -E -dM ${CFLAGS:-""} |
awk -v KIND=$KIND '
    $1 != "#define" || $2 ~ /\(/ || $3 == "" {next}
    $2 ~ /^_/ {next}
    $2 ~ /^[a-z]/ {next}
    $2 ~ /^SOCK_/ && KIND ~ "SocketType" {printf "pub const %s = SocketType(C.%s)\n", tolower($2), $2}
    $2 ~ /^(SOL|IPPROTO)_/ && KIND ~ "SocketLevel" {printf "pub const %s = SocketLevel(C.%s)\n", tolower($2), $2}
    $2 ~ /^(SO|IP|IPV6)_/ && KIND ~ "SocketOption" {printf "pub const %s = SocketOption(C.%s)\n", tolower($2), $2}
    $2 ~ /^AF_/ && KIND ~ "AddrFamily"   {printf "pub const %s = AddrFamily(C.%s)\n", tolower($2), $2}
    $2 ~ /^AI_/ && KIND ~ "AddrInfoFlag" {printf "pub const %s = AddrInfoFlag(C.%s)\n", tolower($2), $2}
    $2 ~ /^NI_/ && KIND ~ "NameInfoFlag" {printf "pub const %s = NameInfoFlag(C.%s)\n", tolower($2), $2}
    KIND ~ "Any" {printf "%s\n", $0}
    {next}' | sort -k 2 -V